Cable tension apparatus.



PATBNTED DBG. 18, 1906. T. S. MILLER.& J. H. DICKINSON.

CABLE TENSION APPARATUS.

Arrmoulon FILED nmz 2s. 190e.

2 SHEETS-snm 2.

m: Nonms Perses co., wnmucrov. b. t.

. UNITED. sTATEs PATENT oEEroiE.

THOMAS SPENCER MILLER, OF SOUTH ORANGE, AND JOSEPH H.

' DlOKINSON, MONTCLAIR, NEW JERSEY.

GABLE TENSION APPARATUS.

Specification of Letters Patent.

' Patented Decgrs, 190e.

Application filed June 23,1906. Serial No. 323.013.

v sEPH H. DroKrNsoN, a resident of Montclair,

inthe county of Essex and State of New Jersey, citizens of the United States, have invented certain new and useful Improvements in Cable Tension Apparatus, of which the following is a specification.

This invention relates to tension apparatus, and has particular application to a novel and useful type of tension apparatus adapted to be employed in connection with cables and cableways.

The invention consists in the construction, combination, and arrangement of parts set forth in and falling within the scope of the appended claims.

. In hoisting apparatus of the class commonly known as cableways the load is usually carried by means of a lcarriage moving along a rope or ropes forming part of a system. It frequently happens that the load placed upon the carriage is more than the trackway along which the carriage runs is able to sustain, and the consequence is that such rope or ropes forming the trackway are liable to be broken, and thus cause the dismantlin 'of the apparatus and the interruption of t e work. Especially is this the case in cableways employed in logging operations, and in the present instance and in the annexed drawings we have shown merely by way of illustration our apparatus used in connection with a cableWay-skidder for hauling logs. It is our intention to provide a type of engine designed to have connected thereto and operated thereby a rope or cable, such engine, in addition to any other function it might perform, being also capable of maintaining a certain tension upon alrope or cable, so that in case the load or strain on the cable shouldl become too, great instead of such cable snapping or breaking the drum tension will be automatically released and the cable will yield or give a suiiicient degree.

In the accom anying drawings, Figurel is a view in side e evation of a portion of a cableway, showing our invention ap iplied thereto. 2 is a top plan view o an engine embraclng our improvements, certain 'well'- known portions of the engine being omitted.

Referring now to Fig. 1, 5 indicates the head or spartree. 6 is themaincable along audi y which the carriage 7 travels. 8 is the outhaul rope for hauling the carriage outward along the cable. 9 indicates the inhaul and the slack-pulling rope, while 10'is the hauling-rope carrying the .gripping-tongs 11. The outhaul ro e 8 passes over a sheave 12 and is operated y the engine-drum 13 of the engine A. 14 and 15 are blocks for the inhaul or slack-pulling rope 9, driven from the drum 16 of the engine. The main cableway 6, which in the present instance is shown as -provided wlth a continuation or extension' 6a, passes over a sheave-block 17, carried by the head-tree, and such extension is provided with the running tensiondevice 18, formed by the blockmembers 19 and the tensionrope 20, reeved therethrough.4 '21 is la loop for anchoring the main cable to a stump or vother anchorage 231'.. Now in the present instance it is the main cable, here comprising the cable 6 and its extension 6a, that it is desired to tension, and, as has been described, the running connection 18 forms a tension device, andthe tension placed upon the cable may be-regulated by operating-'the ro e 20 from the engine. This is done as -foflowsz The engine A is provided with the usual frame,. steam-cylinders, and other parts,

which are too well known to require descrlption, and is'also provided with a power-shaft 24, carrying the pinion-wheel 25, intermeshing with the large gear-wheel 26 upon the shaft of the loading-drums 27, so'that the drum-shaft is thus operated. This power shaft 24 also carries clutches embodying a pinion clutch member 28, loosely mounted thereon, and the clutch member 29, ke ed to revolve with said sha t and to slide a ong the same to be thrown to and out of clutching engagement with the pinion member-28 in a manner well understood. Loose ini'nclutch members 28 mesh in turn with the large gear-wheels 30 of the tension-drums 31 on the shaft 32. Each drum is of the fric- -section 34 and move the v ICO IOS

same into its frictional en agement. A circular rack 37 is arrange large gear 30 on each drum. A pawl 38 coacts with' said rack to hold the same in engagement therewith and prevent the drumsection 33, with its large gear, from turning at certain times. The tension-rope is clesigned to be wrapped aboutone of the drums 31 and to be operated thereby. In Fig. 2 we have shown two such drums 31, the reason for thisbeing that in cableways, such as shown in Fig. .1, there may be emplo ed two or more tension devices for main ca le, so that the raising and lowering of the latter and the changing of the cables may proceed without any reat interruption; but it is to be understood t at, if necessary, we may emplo but one of the tensiorbdrums 31.

'lille above is a description of the construction of the engine, and we will now proceed to describe its function and operation.

Let it be Supposed that the main cable is to be erected to withstand a strain of forty thousand pounds. The 4drum-section 34, around which the cable is wrapped, is moved into frictional engagement with the drum- 5 section 33 by means of setting device 35 and is set so that the frictional engagement between the. two surfaces will not hold and the section 31 will slip against the section 33 at any strain over forty thousand pounds. The clutch 29 is then thrown into operative engagement with the pinion-clutch member 28. and the engine started to wind the tensicn'rope 20. 'When the rope has been propelly tensioned, the clutch member 29 is thrown into its inoperative position and the pawl or dog 38 moved to lock in the ratchetwheel 37, and thus hold the drum 31 against revolution, the two sections 34 and 33 being interlocked by the friction. Now so long as the load upon the carriage is under forty thousand pounds 4in the example given the two drum-sections 34 and 33 will continue to be frictionally interlocked; -but should the londe-fol'- instance, the log-go over forty thousand pounds, and thus place. an abnormal strain upon the main cableway, the frictiomface of. the drum-section 34 will slip relative to the section 3?., and the load wil thus tend to drag or pull the cable toward the round, owing to the slipping or turning of t e drum-sect1on 34. When the tension has suiiiciently slackened, so that the strain upon the cable does not amount to more than forty thousand pounds, again the slipping of the Section 34 will cease, and the friction will again take hold. In some instances under very heavy load the main cable would probably be dragged or pulled downward until it reached the round; but there would be no Snopplng or Vreaking of the same, owing to the tenslon release just described.y This is a great saving, not only as concerns the breakmg of the cable itself, but the time and labor adjacent to the 'variation in the structural features ma construction herein enumerated; -but We wish it to be understood that it may be used for divers purposes, and that modification and be made without departing from the -spirlt of the invention or scope of the claims.

What we claim is- 1. The combination of a sup ort, a cable, a tension-line for said cable, an means operating said tension-line to maintain a predetermined tension on the cable under a certain load and to release the tension on lthe cable when the load thereon exceeds a certain limit.

2. The combination with a support,a cable, tension means therefor, and means 4con-- trolling the tension means to maintain a predetermined tension on the cable u to a certain limit of strain and to release t e tension on the cable when such limit of strain is exceeded.

3. The combination of a su port, a cable, a tension-line connected to said) cable, a drum part about which said tension-line is wrapped a second drum part adapted to be moved into and out of contact with the first drum part and adapted to be moved relative thereto when in contact to release the tension on the cable when the strain or load on the cable exceeds a predetermined limit.

4. The combination with a cable, of means for tensioning the same comprising an engine Iupon the cable exceeds a predetermined limit.

5. The combination of a cable, a drum part, means for locking said part against rotation, a second drum part carrying the cable and ada ted to be shifted into and out of frictional) contact with the flrst-mentioned drum, and to slip or shift relative to the first drum partwhen the strain on the cable exceeds a predetermined limit.

6; The combination of two drum parts, means for locking one of said drum arts IOO IIO

against movement, and vmeans for shifting the other drum part into frictional engagement so that the friction contact wlll be maintained up to a certain strain but such vdrums will slip at a strain beyond that predetermined limit.

7. The combination with a cable or rope, means for tensionin the same comprising an engine having a p urality of drum parts, means for shifting said arts into frictional engagement to mterloc the drums and maintain a desired tension upon the rope under a predetermined strain, and means for permitting s'aid drums to slip relative to each other to release the tension when the strain upon the cable exceeds a certain limit.

8. The combinationof a su port, a main cable, a tension-line connecte to the main cable, a drum art about which said tensionrunning-block for said line, a drum member for o erating the tension-line, a second drum mem er ada ted to be shifted into interlocking frictionafengagement with the first-mentioned drum, member to interlock therewith and maintain a desired tension upon the tension-line and cable, said drum parts slipping relative to each other when the strain upon the cable exceeds a 'redetermined limit. v

10. The combination of a cable, means for supporting the same, and means for maintalrung said'cable at a desired tension under a predetermined strain or load, and releasing the tension upon said cable when the strain or lload thereon exceeds the predetermined limit.

In testimony whereof we have signed our names to this specification in the presence of two subscribing witnesses.

THOMAS SPENCER MILLER. JOSEPH H. DICKINSON.

Witnesses:

y H. T. BARRINGTON, I ERNEST PULsFoRD. 

